package org.bouncycastle.asn1.x509;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.ASN1TaggedObject;
import org.bouncycastle.asn1.DERBitString;
import org.bouncycastle.asn1.DERInteger;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;

/**
 * an X509Certificate structure.
 * 
 * <pre>
 *  Certificate ::= SEQUENCE {
 *      tbsCertificate          TBSCertificate,
 *      signatureAlgorithm      AlgorithmIdentifier,
 *      signature               BIT STRING
 *  }
 * </pre>
 */
@SuppressWarnings({ "deprecation" })
public class X509CertificateStructure extends ASN1Encodable implements
        X509ObjectIdentifiers, PKCSObjectIdentifiers {
    ASN1Sequence seq;
    TBSCertificateStructure tbsCert;
    AlgorithmIdentifier sigAlgId;
    DERBitString sig;

    public static X509CertificateStructure getInstance(ASN1TaggedObject obj,
            boolean explicit) {
        return getInstance(ASN1Sequence.getInstance(obj, explicit));
    }

    public static X509CertificateStructure getInstance(Object obj) {
        if (obj instanceof X509CertificateStructure) {
            return (X509CertificateStructure) obj;
        } else if (obj != null) {
            return new X509CertificateStructure(ASN1Sequence.getInstance(obj));
        }

        return null;
    }

    public X509CertificateStructure(ASN1Sequence seq) {
        this.seq = seq;

        //
        // correct x509 certficate
        //
        if (seq.size() == 3) {
            tbsCert = TBSCertificateStructure.getInstance(seq.getObjectAt(0));
            sigAlgId = AlgorithmIdentifier.getInstance(seq.getObjectAt(1));

            sig = DERBitString.getInstance(seq.getObjectAt(2));
        } else {
            throw new IllegalArgumentException(
                    "sequence wrong size for a certificate");
        }
    }

    public TBSCertificateStructure getTBSCertificate() {
        return tbsCert;
    }

    public int getVersion() {
        return tbsCert.getVersion();
    }

    public DERInteger getSerialNumber() {
        return tbsCert.getSerialNumber();
    }

    public X509Name getIssuer() {
        return tbsCert.getIssuer();
    }

    public Time getStartDate() {
        return tbsCert.getStartDate();
    }

    public Time getEndDate() {
        return tbsCert.getEndDate();
    }

    public X509Name getSubject() {
        return tbsCert.getSubject();
    }

    public SubjectPublicKeyInfo getSubjectPublicKeyInfo() {
        return tbsCert.getSubjectPublicKeyInfo();
    }

    public AlgorithmIdentifier getSignatureAlgorithm() {
        return sigAlgId;
    }

    public DERBitString getSignature() {
        return sig;
    }

    public DERObject toASN1Object() {
        return seq;
    }
}
